DNA strand displacement gates can be used to emulate arbitrary chemical
reactions, and a number of different schemes have been proposed to achieve this.
Here we develop modular correctness proofs for strand displacement emulations of
chemical reaction networks and show how they may be applied to two-domain strand
displacement systems. Our notion of correctness is serializability of interleaved
reaction encodings, and we infer this global property from the properties of the
gates that emulate the individual chemical reactions. This allows correctness to
be inferred for arbitrary systems constructed using these components, and we
illustrate this by applying our results to a two-domain implementation